﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace CommonNet48.DataCheckUtils
{
    /// <summary>
    /// 帧数据校验
    /// </summary>
    public class DataCheckHelper
    {
        #region Sum
        /// <summary>
        /// 计算检验和（一字节）
        /// </summary>
        /// <param name="arrayBytes"></param>
        /// <returns></returns>
        public static byte CheckSumL_1B(IEnumerable<byte> arrayBytes)
        {
            return Convert.ToByte(arrayBytes.Sum(t => t) % 0x100);
        }
        /// <summary>
        /// 计算校验和（二字节，高位在前低位在后）
        /// </summary>
        /// <param name="byteList">校验字节集合</param>
        /// <returns></returns>
        public static byte[] CheckSumHL_2B(IList<byte> bytes)
        {
            int sum = bytes.Sum(t => t);
            return new byte[2] { Convert.ToByte((sum / 0x100) % 0x100), Convert.ToByte(sum % 0x100) };
        }

        /// <summary>
        /// 计算校验和（二字节，高位在前低位在后）
        /// </summary>
        /// <param name="bytes">校验字节集合</param>
        /// <param name="offset">偏移</param>
        /// <returns></returns>
        public static byte[] CheckSumHL_2B(IList<byte> bytes, int offset)
        {
            int sum = bytes.Skip(offset).Sum(t => t);
            return new byte[2] { Convert.ToByte((sum / 0x100) % 0x100), Convert.ToByte(sum % 0x100) };
        }

        /// <summary>
        /// 计算校验和（二字节，高位在前低位在后）
        /// </summary>
        /// <param name="bytes">校验字节集合</param>
        /// <param name="offset">偏移</param>
        /// <param name="length">长度</param>
        /// <returns></returns>
        public static byte[] CheckSumHL_2B(IList<byte> bytes, int offset, int length)
        {
            int sum = bytes.Skip(offset).Take(length).Sum(t => t);
            return new byte[2] { Convert.ToByte((sum / 0x100) % 0x100), Convert.ToByte(sum % 0x100) };
        }

        /// <summary>
        /// 计算校验和（四字节，高位在前低位在后）
        /// </summary>
        /// <param name="bytes">字节集合</param>
        /// <param name="offset">偏移</param>
        /// <param name="length">长度</param>
        /// <returns></returns>
        public static byte[] CheckSumHL_4B(IList<byte> bytes, int offset, int length)
        {
            int sum = bytes.Skip(offset).Take(length).Sum(t => t);
            return BitConverter.GetBytes(sum).Reverse().ToArray();
        }

        /// <summary>
        ///  计算校验和（四字节，高位在前低位在后）
        /// </summary>
        /// <param name="bytes">字节集合</param>
        /// <returns></returns>
        public static byte[] CheckSumHL_4B(IList<byte> bytes)
        {
            int sum = bytes.Sum(t => t);
            return BitConverter.GetBytes(sum).Reverse().ToArray();
        }

        #endregion

        #region CRC
        /// <summary>
        /// CRC32查表
        /// </summary>
        private static readonly uint[] crc32table = new uint[256]{

                0x00000000, 0x77073096, 0xee0e612c, 0x990951ba,
                0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
                0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
                0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
                0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de,
                0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
                0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec,
                0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,

                0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
                0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
                0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940,
                0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
                0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116,
                0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
                0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
                0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,

                0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a,
                0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
                0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818,
                0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
                0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
                0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
                0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c,
                0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,

                0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2,
                0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
                0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
                0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
                0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086,
                0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
                0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4,
                0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,

                0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
                0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
                0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8,
                0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
                0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe,
                0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
                0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
                0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,

                0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252,
                0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
                0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60,
                0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
                0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
                0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
                0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04,
                0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,

                0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a,
                0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
                0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
                0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
                0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e,
                0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
                0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c,
                0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,

                0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
                0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
                0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0,
                0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
                0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6,
                0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
                0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
                0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
            };

        private static readonly uint[] CRC16_CCITT_table = new uint[256]
        {
            0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50a5, 0x60c6, 0x70e7,
            0x8108, 0x9129, 0xa14a, 0xb16b, 0xc18c, 0xd1ad, 0xe1ce, 0xf1ef,
            0x1231, 0x0210, 0x3273, 0x2252, 0x52b5, 0x4294, 0x72f7, 0x62d6,
            0x9339, 0x8318, 0xb37b, 0xa35a, 0xd3bd, 0xc39c, 0xf3ff, 0xe3de,
            0x2462, 0x3443, 0x0420, 0x1401, 0x64e6, 0x74c7, 0x44a4, 0x5485,
            0xa56a, 0xb54b, 0x8528, 0x9509, 0xe5ee, 0xf5cf, 0xc5ac, 0xd58d,
            0x3653, 0x2672, 0x1611, 0x0630, 0x76d7, 0x66f6, 0x5695, 0x46b4,
            0xb75b, 0xa77a, 0x9719, 0x8738, 0xf7df, 0xe7fe, 0xd79d, 0xc7bc,
            0x48c4, 0x58e5, 0x6886, 0x78a7, 0x0840, 0x1861, 0x2802, 0x3823,
            0xc9cc, 0xd9ed, 0xe98e, 0xf9af, 0x8948, 0x9969, 0xa90a, 0xb92b,
            0x5af5, 0x4ad4, 0x7ab7, 0x6a96, 0x1a71, 0x0a50, 0x3a33, 0x2a12,
            0xdbfd, 0xcbdc, 0xfbbf, 0xeb9e, 0x9b79, 0x8b58, 0xbb3b, 0xab1a,
            0x6ca6, 0x7c87, 0x4ce4, 0x5cc5, 0x2c22, 0x3c03, 0x0c60, 0x1c41,
            0xedae, 0xfd8f, 0xcdec, 0xddcd, 0xad2a, 0xbd0b, 0x8d68, 0x9d49,
            0x7e97, 0x6eb6, 0x5ed5, 0x4ef4, 0x3e13, 0x2e32, 0x1e51, 0x0e70,
            0xff9f, 0xefbe, 0xdfdd, 0xcffc, 0xbf1b, 0xaf3a, 0x9f59, 0x8f78,
            0x9188, 0x81a9, 0xb1ca, 0xa1eb, 0xd10c, 0xc12d, 0xf14e, 0xe16f,
            0x1080, 0x00a1, 0x30c2, 0x20e3, 0x5004, 0x4025, 0x7046, 0x6067,
            0x83b9, 0x9398, 0xa3fb, 0xb3da, 0xc33d, 0xd31c, 0xe37f, 0xf35e,
            0x02b1, 0x1290, 0x22f3, 0x32d2, 0x4235, 0x5214, 0x6277, 0x7256,
            0xb5ea, 0xa5cb, 0x95a8, 0x8589, 0xf56e, 0xe54f, 0xd52c, 0xc50d,
            0x34e2, 0x24c3, 0x14a0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
            0xa7db, 0xb7fa, 0x8799, 0x97b8, 0xe75f, 0xf77e, 0xc71d, 0xd73c,
            0x26d3, 0x36f2, 0x0691, 0x16b0, 0x6657, 0x7676, 0x4615, 0x5634,
            0xd94c, 0xc96d, 0xf90e, 0xe92f, 0x99c8, 0x89e9, 0xb98a, 0xa9ab,
            0x5844, 0x4865, 0x7806, 0x6827, 0x18c0, 0x08e1, 0x3882, 0x28a3,
            0xcb7d, 0xdb5c, 0xeb3f, 0xfb1e, 0x8bf9, 0x9bd8, 0xabbb, 0xbb9a,
            0x4a75, 0x5a54, 0x6a37, 0x7a16, 0x0af1, 0x1ad0, 0x2ab3, 0x3a92,
            0xfd2e, 0xed0f, 0xdd6c, 0xcd4d, 0xbdaa, 0xad8b, 0x9de8, 0x8dc9,
            0x7c26, 0x6c07, 0x5c64, 0x4c45, 0x3ca2, 0x2c83, 0x1ce0, 0x0cc1,
            0xef1f, 0xff3e, 0xcf5d, 0xdf7c, 0xaf9b, 0xbfba, 0x8fd9, 0x9ff8,
            0x6e17, 0x7e36, 0x4e55, 0x5e74, 0x2e93, 0x3eb2, 0x0ed1, 0x1ef0
        };

        public static ushort Get_CRC16_CCITT_byTable(ushort CRC_acc, IList<byte> pData, int nLength)
        {
            ushort cRc_16;
            cRc_16 = CRC_acc;
            int index = 0;
            while (nLength > 0)
            {
                cRc_16 = (ushort)((cRc_16 << 8) ^ CRC16_CCITT_table[((cRc_16 >> 8) ^ pData[index]) & 0xff]);
                nLength--;
                index++;
            }
            return cRc_16;
        }

        /// <summary>
        /// CRC32查表校验
        /// </summary>
        /// <param name="byteList"></param>
        /// <returns></returns>
        public static byte[] CheckCRC32(IList<byte> byteList, int offset, int Length)
        {
            long CRC32_data = 0xFFFFFFFF;
            for (int i = offset; i < Length; ++i)
            {
                long t = (CRC32_data ^ byteList[i]) & 0xFF;
                CRC32_data = ((CRC32_data >> 8) & 0xFFFFFF) ^ crc32table[t];
            }
            long data = ~CRC32_data;
            return BitConverter.GetBytes((uint)data).Reverse().ToArray();
        }

        /// <summary>
        /// CRC-ModBus校验和
        /// </summary>
        /// <param name="bytes"></param>
        /// <returns></returns>
        public static byte[] CRCModBus(List<byte> byteList)
        {
            ushort crc = 0xFFFF;// Initial value
            for (int i = 0; i < byteList.Count; i++)
            {
                crc ^= byteList[i];
                for (int j = 0; j < 8; j++)
                {
                    if ((crc & 1) > 0)
                        crc = (ushort)((crc >> 1) ^ 0xA001);// 0xA001 = reverse16(0x8005) 
                    else
                        crc = (ushort)(crc >> 1);
                }
            }
            return BitConverter.GetBytes(crc);
        }

        /// <summary>
        /// CRC16(高位在前)
        /// </summary>
        /// <param name="bytes">校验字节集合</param>
        /// <returns></returns>
        public static byte[] CRC16HL(IList<byte> bytes)
        {
            int length = bytes.Count;
            if (length > 0)
            {
                ushort crc = 0xFFFF;

                for (int i = 0; i < length; i++)
                {
                    crc = (ushort)(crc ^ (bytes[i]));
                    for (int j = 0; j < 8; j++)
                    {
                        crc = (crc & 1) != 0 ? (ushort)((crc >> 1) ^ 0xA001) : (ushort)(crc >> 1);
                    }
                }
                byte hi = (byte)((crc & 0xFF00) >> 8);  //高位置
                byte lo = (byte)(crc & 0x00FF);         //低位置

                return new byte[] { hi, lo };
            }
            else
            {
                return new byte[] { 0, 0 };
            }
        }

        /// <summary>
        /// CRC16(高位在前)
        /// </summary>
        /// <param name="bytes">校验字节集合</param>
        /// <param name="offset">偏移</param>
        /// <param name="length">校验长度</param>
        /// <returns></returns>
        public static byte[] CRC16HL(IList<byte> bytes, int offset, int length)
        {
            byte[] data = bytes.Skip(offset).Take(length).ToArray();
            if (length > 0)
            {
                ushort crc = 0xFFFF;

                for (int i = 0; i < length; i++)
                {
                    crc = (ushort)(crc ^ (data[i]));
                    for (int j = 0; j < 8; j++)
                    {
                        crc = (crc & 1) != 0 ? (ushort)((crc >> 1) ^ 0xA001) : (ushort)(crc >> 1);
                    }
                }
                byte hi = (byte)((crc & 0xFF00) >> 8);  //高位置
                byte lo = (byte)(crc & 0x00FF);         //低位置
                return new byte[] { hi, lo };
            }
            else
            {
                return new byte[] { 0, 0 };
            }
        }

        /// <summary>
        /// CRC16(低位在前)
        /// </summary>
        /// <param name="bytes">校验字节集合</param>
        /// <returns></returns>
        public static byte[] CRC16LH(IList<byte> bytes)
        {
            int length = bytes.Count;
            if (length > 0)
            {
                ushort crc = 0xFFFF;

                for (int i = 0; i < length; i++)
                {
                    crc = (ushort)(crc ^ (bytes[i]));
                    for (int j = 0; j < 8; j++)
                    {
                        crc = (crc & 1) != 0 ? (ushort)((crc >> 1) ^ 0xA001) : (ushort)(crc >> 1);
                    }
                }
                byte hi = (byte)((crc & 0xFF00) >> 8);  //高位置
                byte lo = (byte)(crc & 0x00FF);         //低位置
                return new byte[] { lo, hi };
            }
            else
            {
                return new byte[] { 0, 0 };
            }
        }

        /// <summary>
        /// CRC16(低位在前)
        /// </summary>
        /// <param name="bytes">校验字节集合</param>
        /// <param name="offset">偏移</param>
        /// <param name="length">校验长度</param>
        /// <returns></returns>
        public static byte[] CRC16LH(IList<byte> bytes, int offset, int length)
        {
            byte[] data = bytes.Skip(offset).Take(length).ToArray();
            if (length > 0)
            {
                ushort crc = 0xFFFF;

                for (int i = 0; i < length; i++)
                {
                    crc = (ushort)(crc ^ (data[i]));
                    for (int j = 0; j < 8; j++)
                    {
                        crc = (crc & 1) != 0 ? (ushort)((crc >> 1) ^ 0xA001) : (ushort)(crc >> 1);
                    }
                }
                byte hi = (byte)((crc & 0xFF00) >> 8);  //高位置
                byte lo = (byte)(crc & 0x00FF);         //低位置

                return new byte[] { lo, hi };
            }
            else
            {
                return new byte[] { 0, 0 };
            }
        }
        #endregion
    }
}
